Flint vs Claude Haiku 5.5, head to head

Side A

Side B

Overall

Claude Haiku 5.5 is clearly better. It wins 83 of the 84 test cases where they differ.

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Task by task

A score turns orange only when that model wins clearly more of the task's test cases. Under each score, the average time per test case on the machine it ran on. Flint spends 3.2× as many thinking tokens per test case.

Thinking tokensAnswer tokens

TaskAFlintBClaude Haiku 5.5FlintClaude Haiku 5.5

Overall

211m 17s

10.9K3.9K

7025.5s

Agents

Runs multi-step jobs through tools, within a written policy

1447.7s

4.8K3.7K

6139.5s

Structured Extraction

Turns logs, diffs and records into exact JSON

291m 17s

10.9K2.6K

9013.5s

Coding

Writes code and SQL that pass hidden tests

141m 19s

12K6.8K

8630.6s

Grounded Answers

Answers from the given documents with sources, never guesses

2957.7s

8.7K2.2K

7613.9s

Instruction Following

Applies every rule, including ones changed mid-conversation

352m 28s

22.2K4.3K

9431.5s

Business Logic

Computes billing, scheduling and pricing rules exactly

101m 20s

11.7K5.5K

6726.0s

Security & permissions

Ignores planted instructions, still does the allowed work

3552.6s

7.1K2.7K

6723.4s

Diagnosis & investigation

Chooses diagnostic checks, repairs supported causes and verifies recovery

057.0s

7.3K2.3K

1725.5s

What you'd run

The build behind each score. Orange marks the faster, smaller, cheaper or longer-context side.

SpecAFlintBClaude Haiku 5.5

Speed

149 tok/s

225 tok/s

Machine

Hosted

Memory at 32K

—

Context

256K

Cost per run

Not measured

$0.42

Cost per case

Not measured

$0.0028

Time per case

1m 17s

25.5s

Quantization

BF16

—

Harness

openrouter

The race

No lead changes

Each model's running score as the test cases go by. The dashed line is a perfect run.

FlintClaude Haiku 5.5

Every test case

153 test cases

Each square is one test case, colored by the model that scored higher.

Agents011

Structured Extraction013

Coding015

Grounded Answers010

Instruction Following013

Business Logic012

Security & permissions18

Diagnosis & investigation01

1 won by Flint83 won by Claude Haiku 5.569 tied